Carton forming machine



INVENTOR If BYJ '27 Qauqw ATTOR EY ll lllllr J. G. VERGOBB] CARTON FORMING MACHINE Filed Nov. 2, 1936 Aug. 10, 1937.

Patented Aug. 10, 1937 UNITED STATE CARTON FORMING MAGHINE Application November 2, 1936, Serial No. 108,829

3 Claims.

This invention relates to a carton forming machine and particularly to a machine for making a paraffin lined carton.

The object of the invention is to provide a novel carton forming machine of the type embodying one or more forming blocks around which the carton and liner are formed, and in which provision is made for reducing to a minimum the transfer of paraffin from the liner to the carton by the presser member usually employed in sealing the side seams of both the liner and carton.

With this object in view and such others as may hereinafter appear, the invention consists in the carton forming machine and in the various structures, arrangements and combinations of parts hereinafter described and particularly defined in the claims at the end of this specification.

In the drawing illustrating the preferred embodiment of the invention, Fig. 1 is a side eleva- 2' tion of a portion of a carton forming machine, partly in cross-section; and Fig. 2 is an end view of one of the forming blocks.

The present invention is shown as embodied in a carton forming machine adapted to form the liner and carton upon a forming block and in general the machine is provided with a plurality of forming blocks secured to a central shaft rotated intermittenly to present the forming blocks successively to the various-liner and carton forming stations of the machine. In prior carton lining and forming machines of this type a sheet of inner or lining paper, parafiin coated, is first folded about the forming block to form a tube and the longitudinal edges of said tube are thereafter heat sealed together by softening the paraffin to form the longitudinal seam of the inner liner of the carton and at a succeeding station the extended edges of the liner are folded over on the front face of the forming block to produce the bottom of the liner. At subsequent stations an outer wrapper usually of cardboard is formed over the block and the lining whereupon the composite liner and carton is stripped from the forming block ready to be filled and sealed.

During the formation of the paraffin paper liner about the block, a presser foot is employed to apply pressure upon the overlapping portions of the paper which forms the side seam against the heated forming block. The pressure thus applied serves to melt or soften the parafiin in the paper and causes the, overlapping portions to firmly adhere together.

) One of the principal disadvantages of known machines of this type resides in the fact that the presser foot is liable to pick up some of the softened paraffin and consequently when the same presser foot is again brought into play to seal the outer cardboard wrapper or carton along the side seam, the accumulated parafiin on the presser foot is transferred to the carton causing 5 an sightly carton to be produced and detracting from the commercial value of the machine.

In accordance with the present invention provision is made for regulating the pressure applied to the side seams by the presser foot to limit it 10 to a very light pressure so as to pick up a minimum of parafiin. As a result when the presser foot contacts the side seam of an outer wrapper or carton it will not mark it with accumulated paraffin. 15

Referring now to the drawing, H) represent the usual heated forming blocks secured to a flange l2 which is rotated intermittently upon the central shaft M to present the forming blocks to successive stations in the formation of a composite 2O liner and wrapper. Inasmuch as machines of this type which are provided with mechanisms for wrapping the liner about the forming block and subsequently the outer cardboard wrapper are well known in the packaging trade, only suf ficient portions of the machine have been herein illustrated and will be hereinafter described as will enable the present invention to be understood. Ihe manner of heating the forming blocks I 8, may comprise any of the Well-known methods of heat application, usually by means of electrically heated elements, not shown.

In the usual carton forming machine a paraffin coated liner i6 is wrapped about the block in the manner illustrated in Fig. 2, so as to form overlapping portions i8, 20 against which a presser foot 22 is lowered to seal the longitudinal edges together as hereinbefore stated.

As herein shown, the presser foot 22, preferably faced with a strip of hard felt 25, is pivotally 40 mounted on one arm 26 of a three armed lever loosely mounted on a pin 28 journaled in bearings 30 on the flange 52. The seam presser 22, normally yieldingly urged against the forming block Ill by a spring 32 bearing against an up- 45 standing arm 34 of the three armed lever, is arranged to be rocked to raise and lower it so as to permit the application of the lining sheet or carton forming material about the forming block and subsequently to permit the removal of the 50 lined carton from the block. The three armed lever is arranged to be rocked by connections from a cam 36 fast on a cam shaft 38 which may be driven in any usual or preferred manner, not shown. The cam 36 cooperates with a cam roll 49 5 mounted on one arm 42 of a bell crank pivoted on a shaft 44. The second arm $6 is connected to a slidably mounted member 48 by a link 56). The member 48 is prevented from rotating by a pin 52 secured in a tie piece 54 and extending through a hole in the vertically reciprocated member 38. Another bell crank, loosely mounted on a pin 56 journaled in bearings in the tie piece 5%, is provided with a roller 58 on the end of one arm Ell of the bell crank which cooperates with a slot 52 cut in the member 68. The second arm 6d, also provided with a roller 66, is arranged to engage the third arm 68 of the three armed lever. The cam roller i0 is held against its cam 36 by a spring HI which permits the reciprocating member 48 to be lowered and thereby permits the presser foot 22 to again engage the lining or wrapper about the forming block.

From the description thus far it will'be understood that the paraflin liner is applied at one station, subsequent folding operations at another station and thereafter an outer wrapper or carton is applied which is usually provided'with a strip of glue along one of its overlapping edges against which the seam presser is arranged to bear and after folding over and sealing the bottom of the carton it is stripped off its forming block. It will be understood that although only one presser foot elevating and lowering mechanism has been herein described and illustrated, similar mechanisms are provided at each station where there is occasion to elevate the seam presser.

In order to regulate the pressure of the presser foot against the liner to limit it to a very light pressure, an adjustable stop 12 is provided which is adjustably secured in the arm 26 and which bears against a raised surface It on the forming block it). Adjustment of the pressure against the block is effected by loosening the lock nut iii and turning the screw 72 until the desired pressure is produced. In this manner it is possible to limit the pressure of the seam presser against the lining so that the presser foot will pick up a minimum of parafiin during the lining sealing operation and as a result when the presser foot is again lowered to seal the longitudinal edges of the outer wrapper or carton it will not mark it with accumulated paraffin,

While the preferred embodiment of the invention has been herein illustrated and described, it will be understood that the invention may be embodied in other forms within the scope of the following claims.

Having thus described the invention, what is claimed is:

1. In a carton forming machine, in combination, a forming block about which a parafiin lining sheet and carton forming material are successively wrapped to form a paraflin lined carton, a presser member cooperating with the block to press first a seam oi the liner and then a seam of the carton, and means for limiting the movement of the presser toward the block to thereby cause the presser to press against the lining supported by the block with a light pressure whereby to reduce to a minimum the adherence and accumulation of paraffin to and upon the presser.

2. In a carton forming machine, in combination, a forming block about which a paraffin lining sheet and carton forming material are successively wrapped to form a paraffin lined carton, a presser member cooperating with the block to press first a seam of the liner and then a seam of the carton, and an adjustable stop screw cooperating with the presser and the block to limit the movement of the presser toward the block to thereby cause the presser to vpress against the lining supported by the block with a light pressure whereby to reduce to a minimum the adherence and accumulation of parafiin to and upon the presser.

3. In a carton forming machine, in combination, a forming block about which a paraffin lining sheet and carton forming material are successively wrapped to form a parafiin lined carton, a presser member cooperating with the block to press first a seam of the liner and then a seam of the carton,'and means for adjustably limiting the movement of the presser toward the block to thereby cause the presser to press against the lining supported by the block with a light pressure whereby to reduce to a minimum the adherence and accumulation of paraifin to and upon 

